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Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng Zhu Cun Liu Yiren Yu Guoshu Gao Yumeng Zhao Xiongfu Zhang Guodong Liu Guohui Yang state key laboratory of fine chemicals School of Chemical Engineering Dalian University of Technology state key laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： Aspect ratio

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Visualization of the protective role of estrogen against female liver fibrosis via an ER viscosity NIR fluorescent probe

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Science China Chemistry 2025年第1期 360-368页

作者： Zheng Liu Changyu Zhang Zipeng Li Wanying Ma Jia Liu Xiang Xia Ning Xu Wen Sun Jianjun Du Jiangli Fan Xiaojun Peng state key laboratory of fine chemicals Dalian University of Technology Ningbo Institute of dalian university of technology

Endoplasmic reticulum(ER) viscosity has emerged as a new potential biomarker for hepatic fibrosis(HF). Herein, we report the first ER-targeting viscosity-responsive near-infrared(NIR) fluorescent probe HBT-PP for investigations of HF *** twisted intramolecular charge transfer(TICT) and the excited state intramolecular proton transfer(ESIPT) are combined to endow HBT-PP with the selective response towards viscosity(～62-fold) and a super large stokes shift(～320 nm). HBT-PP mainly targets organelle ER and is able to image the drug-or alcohol-induced viscosity elevation in living cells. Significantly,HBT-PP was successfully applied to visualize the gender difference in HF and the protective role of estrogen in restraining HF progression. Of note, after 10 min of stain with HBT-PP, HF lesions showed a stage-based response, indicating the potential of this probe in fast and early diagnosis of HF. These results clearly demonstrated the promising application of HBT-PP as a new tool for exploring ER viscosity-involved physiological and pathological processes.

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Spin-modulated near-infrared-Ⅰ emission in a xanthene-decorated Fe(Ⅱ) spin-crossover complex

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Science China Chemistry 2025年

作者： Cheng Yi Duyong Chen Shihui Zhang Rui Cai Chunying Duan Yinshan Meng Tao Liu state key laboratory of fine chemicals Frontier Science Center for Smart Materials and Chemical Engineering School of Chemical Engineering Dalian University of Technology Instrumental Analysis Center Dalian University of Technology School of Chemistry Dalian University of Technology Liaoning Binhai laboratory

Molecular materials showing synergetic coupling of near-infrared （NIR） fluorescence and spin-crossover （SCO） are promisingly applicable in in-vivo bioimaging,temperature sensing,and spintronic *** the related study faces formidable *** this work we graft the NIR fluorophore xanthene onto the dipyridyl substituted triazole ligand and construct a new Febased SCO material,{FeⅡ（ddxc-abpt）2[N（CN）2]2}(1,ddxc-abpt:（E）-4-(((3,5-di（pyridin-2-yl）-4H-1,2,4-triazol-4-yl)imino)methyl)-N,N-diethyl-2,3-dihydro-1H-xanthen-6-amine).Magnetic studies indicate that compound 1 exhibits thermally induced SCO property in both the solid and solution ***-temperature fluorescence emission spectra reveal a remarkable 7-fold increase in photoluminescence intensity upon the transition from the low-spin state at 110 K to the high-spin state at 280 K,which is the record of all reported coupled fluorescence-SCO ***-temperature ultraviolet-visible （UV-Vis）absorption spectra show a significant change in absorption intensity within the fluorescence emission window,consistent with the F?rster resonance energy transfer （FRET） ***-dependent density functional theory （TD-DFT） calculations demonstrate that the strong coupling is attributed to disrupted energy transfer between the xanthene fluorophore and high-spin *** work provides a feasible approach for expanding the synergetic SCO-fluorescence materials to the NIR-Iwavelength region,and hopefully contributes to the applications of tunable NIR-SCO molecule-based sensors and devices.

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Electrochemical conversion of methane to bridge the gap in the artificial carbon cycle

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Journal of Energy Chemistry 2025年第1期100卷 286-308页

作者： Yuhao Peng Yuefeng Song Ihar Razanau Juanxiu Xiao Wei Xiao Di Hu Guoxiong Wang College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power Sources Wuhan University state key laboratory of Catalysis Dalian National Laboratory for Clean Energy iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Dalian Institute of Chemical Physics Chinese Academy of Sciences laboratory of Physical-Chemical Technologies SSPA Scientific and Practical Materials Research Centre of NAS of Belarus state key laboratory of Marine Resources Utilization in South China Sea Collaborative Innovation Center of Marine Science and Technology School of Marine Science and Engineering Hainan University Department of Chemical and Environmental Engineering University of Nottingham Ningbo China

Methane, an abundant one-carbon（C1） resource, is extensively used in the industrial production of vital fuels and value-added chemicals. However, current industrial methane conversion technologies are energy-and carbon-intensive, mainly due to the high activation energy required to break the inert C–H bond, low selectivity, and problematic side reactions, including CO2emissions and coke deposition. Electrochemical conversion of methane（ECM） using intermittent renewable energy offers an attractive solution, due to its modular reactor design and operational flexibility across a broad spectrum of temperatures and pressures. This review emphasizes conversion pathways of methane in various reaction systems, highlighting the significance and advantages of ECM in facilitating a sustainable artificial carbon cycle. This work provides a comprehensive overview of conventional methane activation mechanisms and delineates the complete pathways of methane conversion in electrolysis contexts. Based on surface/interface chemistry, this work systematically analyzes proposed reaction pathways and corresponding strategies to enhance ECM efficiency towards various target products, including syngas, hydrocarbons, oxygenates, and advanced carbon materials. The discussion also encompasses opportunities and challenges for the ECM process, including insights into ECM pathways, rational electrocatalyst design, establishment of benchmarking protocols, electrolyte engineering, enhancement of CH4conversion rates, and minimization of CO2emission.

关键词： Activation energy

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Flexible Gradient Poly(ether-ester)from the Copolymerization of Epoxides and c-Caprolactone Mediated by a Hetero-bimetallic Complex

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Chinese Journal of Polymer Science 2021年第8期39卷 1013-1019,I0007页

作者： Wei-Min Ren Hong-Juan Gao Tian-Jun Yue state key laboratory of fine chemicals Dalian University of TechnologyDalian 116024China

Copolymerization is a commonly employed method for optimizing the properties of polymer *** ether segments into polyesters main chain to obtain polyether-polyester copolymers is an effective strategy to realize the integration of multiple properties of polyester and polyether,and to develop more high-performance,multi-purpose polymer ***,the synthesis of poly(ether-ester)s is accessible by employing the biphenyl-linked heterodinuclear salen Cr-AI complex in the presence of PPNCI for the copolymerization of epoxides and£-caprolactone(CL).Monitoring the copolymerization process reveals that catalyst 1 exhibited good performance for the copolymerization of epoxides and CL,affording copolymers with a gradient sequence *** dynamic thermomechanical analysis(DMA)study indicates the obtained poly(ether-ester)s possess enhanced flexibility compared with the block copolymers or blend of PPO and PCL homopolymers with the same *** study provides a theoretical basis for the preparation of high-performance polymer materials.

关键词： Lactone Epoxide Copolymerization Poly(ether-ester)copolymer Dynamic mechanical analysis

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Mechanism-inspired Design of Heterodinuclear Catalysts for Copolymerization of Epoxide and Lactone

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Chinese Journal of Polymer Science 2020年第9期38卷 950-957,I0006页

作者： Wei-Min Ren Rui-Jing Wang Bai-Hao Ren Ge-Ge Gu Tian-Jun Yue state key laboratory of fine chemicals Dalian University of TechnologyDalian 116024China

Polyesters,as a class of high-performance and versatile polymer materials,often suffer from some drawbacks,such as hydrophobicity and brittleness due to their single structure ***,modifications have attracted much attention for enhancing their desirable properties,of which one efficient way is incorporating the aliphatic polyether segment into the main chain of the ***,this approach is of much challenge because the obtained polyesters are problematic in either low alternating degree or low molecular ***,we describe an efficient strategy to incorporate polyether fragment into polyester by developing a novel Co-Al based heterodinuclear complex for mediating the copolymerization of propylene oxide(PO)withε-caprolactone(CL).The tracking experiments reveal that PO and CL convert into the polymer chain throughout the polymerization ***,the linear increase in the molecular weight with conversion of CL indicates the controllable nature of the *** competition polymerization,offering the monomer reactivity ratios of rCL=0.96 and rPO=1.04,suggests that the tendency of self-propagation or incorporation of monomers is nearly ***,the obtained polymers with different ether contents exhibit tunable thermal properties with enhanced decomposition temperature for the polymer with higher ether *** newly developed heterodinuclear complex for new polymerization provides an idea to synthesize new functional polymeric materials.

关键词： Heterodinuclear catalysis Polyester-polyether copolymer Lactone Epoxide Copolymerization

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Partners in Epoxide Copolymerization Catalysis:Approach to High Activity and Selectivity

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Chinese Journal of Polymer Science 2022年第11期40卷 1331-1348页

作者： Xiao-Bing Lu Bai-Hao Ren state key laboratory of fine chemicals Dalian University of TechnologyDalian 116024China

The ring-opening alternating copolymerization processes of epoxides with small-molecule monomers,such as carbon dioxide(CO_(2)),carbonyl sulfide(COS)and cyclic anhydrides,are powerful strategies for preparing polymeric materials with degradable carbonate/ester/thiocarbonate main-chain backbone *** catalysts selected for copolymerization processes play crucial roles in determining their reaction rates and productivities,as well as the selectivity,regio-and stereochemistry,compositions,and the molecular weights of their resultant *** processes often generate undesirable byproducts such as polyether or ether linkages dispersed randomly within the copolymer's chain,and/or more thermodynamically stable cyclic *** this account,we outline our efforts of over a dozen years on developing highly active well-defined metal catalysts based on inter-and intra-molecular synergistic strategies to selectively produce completely alternating copolymers from epoxides and various small-molecule *** attention was paid to the enantioselective resolution copolymerization processes of racemic epoxides via regioselective ring-openings,and the asymmetric copolymerization processes of meso-epoxides with CO_(2),COS,or cyclic anhydrides via dissymmetrical ring-openings using multichiral catalytic systems,and affording isotactic copolymers with main-chain *** addition,this account provides a thorough mechanistic understanding of the high reactivities,excellent selectivity,and unprecedented stereochemical controls of these copolymerization systems,mediated by interand intramolecular synergistic catalysis.

关键词： Epoxide Ring-opening copolymerization Synergistic catalysis CO_(2) Stereochemistry control

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Selective catalytic reduction of NO by C_2H_2 over Ce-Al_2O_3 catalyst with rate-determining step of NO oxidation

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Journal of Natural Gas Chemistry 2012年第3期21卷 332-338页

作者： Suhua Yan Xinping Wang Wenchen Wang Zequn Liu Jiahao Niu state key laboratory of fine chemicals Dalian University of TechnologyDalian 116024LiaoningChina

Ce-A12O3 catalysts prepared by co-precipitation are investigated both in NO oxidation by 02 and in selective catalytic reduction of NO by C2H2 （C2H2-SCR）. It is found that C2H2-SCR is initiated and controlled by NO oxidation to NO2 over A12O3. Ce loading on A12O3 is almost inactive for NO oxidation below 350℃, since NO2 strongly adsorbs on cerium oxide, leading to the active sites being blocked, which was characterized by temperature-programmed desorption of NO and NO2 and Fourier transform infrared spectroscopy after NO＋O2 coadsorption over the samples. However, in the case of C2H2-SCR, Ce loading on A1203 significantly improves the reaction by accelerating the NO oxidation step in the temperature range of 250-450℃, since the nitrate species produced by NO2 adsorption is an active intermediate required by C2H2-SCR.

关键词： NOx removal NO oxidation nitrate species Ce-A1203 acetylene

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Sequence-activated chemiluminescence probes: programmable illumination for high-contrast in vivo sensing and imaging

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Science China Chemistry 2025年第01期 26-34页

作者： Yutao Zhang Juan Li Wei-Hong Zhu Zhiqian Guo Shanghai key laboratory of Functional Materials Chemistry Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Institute of Fine Chemicals School of Chemistry and Molecular Engineering East China University of Science and Technology state key laboratory of Bioreactor Engineering Shanghai Frontier Science Research Base of Optogenetic Techniques for Cell MetabolismEast China University of Science & Technology

Sequence-activated chemiluminescence(CL) technique offers a unique approach to detecting specific biomolecules or cellular events with high sensitivity and spatial resolution. The fundamental principle behind sequence-activated CL probes involves tailoring highly-controllable CL signals in response to specific sequences or events of interest, thus enabling high-contrast signals under complex physiological conditions. This sequential activation could be triggered by enzymes, reactive oxygen species(ROS), biothiols or changes in the microenvironment. These unique sequence-activated CL probes bestow several advantages, including minimal background, deep-tissue penetration, and the ability of non-invasive or minimally invasive detection. The sequence-activated CL techniques represent a significant advancement in molecular imaging and diagnostics. In this mini-review, we focus on the latest developments in sequential CL probes, addressing the technical challenges and discussing the future trajectory by harnessing CL signaling and molecular recognition.

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Kinetic analysis of experiment data for the formation of *** Blue 9 leuco compound

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Chinese Journal of Chemical Engineering 2017年第10期25卷 1422-1426页

作者： Rongwen Lu Ziang Zhao Xinyu Hao Beibei Shao Shufen Zhang state key laboratory of fine chemicals Dalian University of Technology Dalian 116024 China

A systematic study of the synthesis of *** Blue 9 leuco compound in water is *** kinetic analysis of experimental data for the condensation reaction between 2-formylbenzenesulfonic acid sodium and N-ethyl-N-(3'-sulfonic acid benzyl) aniline obtained at four different temperatures ranging between 85 and 100°C is *** is shown that the reaction followed second-order rate *** overall rate constant(k) increased with the increase of *** the basis of the value of k,activation energy(E_a) of the reaction was ***,it is found that reactant concentration has great effect on the formation of *** Blue 9 leuco compound,implying that it is not enough to improve the conversion of N-ethyl-N-(3'-sulfonic acid benzyl) aniline by only prolonging reaction time in the late period of the reaction.

关键词： Triphenylmethane dyes C.I.Acid blue 9 leuco compound Kinetics Condensation

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